Fuel container for a motor vehicle

ABSTRACT

A fuel container for a motor vehicle has a structural unit that includes of a separator and an activated carbon filter that forms a ventilation device. The structural unit is attached in a chamber for the collection of fuel and has common container for the retention of the separator and the activated carbon filter. The container is mounted on a fuel conveyance unit.

The invention relates to a fuel tank with a chamber for collecting fuel for a motor vehicle, with a ventilation device, with an activated carbon filter and with a fuel-delivery unit for delivering fuel, the ventilation device having a separator for separating liquid fuel and gases.

Such fuel tanks usually have a multiplicity of individual ventilation lines fitted on the outside of the fuel tank, and such fuel tanks are known in practice. The separator for separating liquid fuel and gases is often arranged on a filler neck of the fuel tank. The activated carbon filter is usually arranged on or in the fuel tank and is connected to the separator via a further ventilation line.

The disadvantage with the known fuel tank is that it is very bulky and that arranging components of the ventilation device outside the fuel tank promotes diffusion of fuel to the surroundings.

The problem on which the invention is based is to develop a fuel tank of the type mentioned in the introduction such that it is a particularly compact construction and largely prevents fuel from escaping into the surroundings.

This problem is solved according to the invention in that the separator and the activated carbon filter are designed in the form of a structural unit, and in that the structural unit is arranged within the chamber.

This configuration allows all the parts of the ventilation device which are connected with liquid or gaseous fuel to be arranged within the fuel tank according to the invention. This results in the fuel tank being of particularly compact configuration. Furthermore, the invention makes it possible for the amount of fuel vapors escaping into the surroundings to be kept to a particularly low level.

The fuel tank according to the invention is particularly straightforward to assemble if the structural unit made up of separator and activated carbon filter is fastened on the fuel-delivery unit. Furthermore, this makes it possible for the structural unit made up of separator and activated carbon filter and the fuel-delivery unit to be inserted into the fuel tank according to the invention through a single installation opening.

The fuel tank according to the invention is of particularly compact configuration if the structural unit made up of separator and activated carbon filter has a common canister with a partition wall for separating the activated carbon filter from the separator.

According to another advantageous development of the invention, the situation where fuel penetrates into the activated carbon filter can be reliably avoided if the separator and the activated carbon filter are connected via a valve, and if the valve is designed as a rollover valve and/or anti-slosh valve. For the design of anti-slosh valve, the valve may have, for example, a float element which, upon contact with liquid fuel, closes the connection between the separator and the activated carbon filter. Designing the valve as a rollover valve prevents fuel from running out through the activated carbon filter when the motor vehicle having the fuel tank according to the invention rolls over.

According to another advantageous development of the invention, the ventilation device requires only a particularly small number of components to be installed if the separator is connected to ventilation lines guided into lateral regions of the chamber.

According to another advantageous development of the invention, liquid fuel can be channeled away out of the separator particularly straightforwardly if a suction jet pump is arranged in the separator, and if the suction jet pump opens out into the chamber.

Another advantageous development of the invention contributes to reducing fuel emissions if the structural unit made up of separator and activated carbon filter is spaced apart from a flange which closes an installation opening in the fuel tank. Furthermore, the structural unit can thus be introduced particularly straightforwardly into the fuel tank according to the invention through the installation opening.

The assembly of the fuel tank according to the invention is further simplified if a fuel-level sensor is arranged on the structural unit made up of separator and activated carbon filter.

According to another advantageous development of the invention, the activated carbon filter can easily be regenerated, in dependence on an envisaged event, if a switchable regeneration valve is arranged in the connection between the separator and the activated carbon filter, and if the regeneration valve is designed for optionally making or breaking the connection. This configuration reliably avoids influencing of the regeneration of the activated carbon filter by gas exchange with the separator.

The generation of the activated carbon filter is further simplified if the activated carbon filter can be connected, via a line guided through the flange, to the surroundings and, by way of a regeneration line, to an internal combustion engine of the motor vehicle.

The invention permits numerous embodiments. In order to demonstrate the basic principle of the invention further, one of these embodiments will be described hereinbelow and is illustrated in the drawing, in which:

FIG. 1 shows, schematically, a sectional illustration through a fuel tank according to the invention,

FIG. 2 shows a view of a ventilation device with a fuel-delivery unit of the fuel tank from FIG. 1,

FIG. 3 shows, schematically, a sectional illustration through a structural unit made up of ventilation device and activated carbon filter along with adjacent regions of the fuel tank from FIG. 1.

FIG. 1 shows a fuel tank 1 for a motor vehicle which is intended for supplying an internal combustion engine (not illustrated) with fuel and has a chamber 2, for collecting fuel, and a filler neck 3. A fuel-delivery unit 4 and a ventilation device 5 are arranged in the fuel tank 1. The ventilation device 5 has a canister 6, which is arranged in the vicinity of the fuel-delivery unit 4, and ventilation lines 7, which lead into lateral regions of the main chamber 2 of the fuel tank 1. The ventilation line 7 may also be provided with further ventilation lines (not illustrated) leading for example into the filler neck 3. The fuel-delivery unit 4 is prestressed against the base of the fuel tank 1 and is supported on a flange 9, which closes an installation opening 8.

FIG. 2 shows, in perspective, the fuel-delivery unit 4 from FIG. 1 with the canister 6 of the ventilation device 5. The canister 6 of the ventilation device 5 is fastened on the fuel-delivery unit 4 and secures a filling-level sensor 10. Furthermore, the canister 6 of the ventilation device 5 is connected to the flange 9 via a line 11, which leads into the surroundings, and via a regenerating line 12. The regenerating line 12 is guided, for example, to an intake tube (not illustrated) of the internal combustion engine.

FIG. 3 shows, in a sectional illustration through the canister 6 of the ventilation device 5, that an activated carbon filter 13 is arranged in the canister 6. The activated carbon filter 13 and the ventilation device 5 thus form a preassemblable structural unit which can be inserted into the fuel tank 1 through the installation opening 8. The canister 6 contains a partition wall 14 for separating a separator 15 from the activated carbon filter 13. The separator 15 separates fuel from gases and has a suction jet pump 16. The suction jet pump 16 is supplied by the fuel-delivery unit 4 from FIG. 1, via a filter 17 and a non-return valve 18, with fuel as a propellant and delivers into the fuel tank 1 fuel which has been collected in the separator 15. The separator 15 is connected to the activated carbon filter 13 via a valve 19. The valve 19 is designed in the form of a rollover valve and prevents fuel from running out of the fuel tank 1 through the activated carbon filter 13, and the line 11 leading into the surroundings from the activated carbon filter 13, when the motor vehicle rolls over. The valve 19 is also designed in the form of an anti-slosh valve and, for example when the vehicle goes round a corner, prevents fuel collected in the separator 15 from sloshing into the activated carbon filter 13. Furthermore, a regeneration valve 20 is arranged in the connection between the separator 15 and the activated carbon filter 13. This regeneration valve 20 can be closed when the activated carbon filter 13 is regenerated. FIG. 3 also shows that the canister 6 of the structural unit made up of separator 15 and activated carbon filter 13 is spaced apart from the flange 9. 

1-10. (canceled)
 11. A fuel tank for a motor vehicle, comprising: a chamber for collecting fuel; a fuel-delivery unit for delivering fuel from the chamber; and a ventilation device having an activated carbon filter and a separator for separating liquid fuel and gases, wherein the separator and the activated carbon filter are configured as a structural unit, the structural unit being arranged within the chamber.
 12. The fuel tank according to claim 11, wherein the structural unit is coupled to the fuel-delivery unit.
 13. The fuel tank as claimed in claim 11, wherein the structural unit has a partition wall for separating the activated carbon filter from the separator.
 14. The fuel tank according to claim 11, wherein the separator and the activated carbon filter are coupled via a valve.
 15. The fuel tank according to claim 11, wherein the separator is coupled to at least one ventilation line guided into the chamber.
 16. The fuel tank according to claim 11, wherein a suction jet pump is arranged in the separator, and the suction jet pump opens out into the chamber.
 17. The fuel tank according to claim 11, wherein the structural unit is spaced apart from a flange configured to close an installation opening in the fuel tank.
 18. The fuel tank according to claim 11, further comprising a fuel-level sensor coupled to the structural unit.
 19. The fuel tank according to claim 11, further comprising a switchable regeneration valve coupled between the separator and the activated carbon filter, the regeneration valve configured to optionally make or break a connection between the separator and the activated carbon filter.
 20. The fuel tank according to claim 11, wherein the activated carbon filter is coupled via a line guided through the flange to an environment surrounding the fuel tank and via a regeneration line to an internal combustion engine.
 21. The fuel tank according to claim 14, wherein the valve is at least one of a rollover valve and an anti-slosh valve. 